Metal coating



March 17, 1925: 1,530,374 F. c. KELLEY METAL COATING Original Filed May10. 1920 Invent or Floyd C. Kelley,

His Attorney Patented Mar. 17-, 1925.

UNITED [STATES PAT'E T OFFICE.

FLOYD o. KELLEY, or scHENEorAnY, NEw YORK, ASSIGNOR TO GENERAL ELEc'rnIcCOMPANY/A CORPORATION our NEW YoEx.

METAL COATING.

Original application filed ma 10, 1920, Serial No. 380,023. Dividedandthis application flied October 12, 1922. Serial No. 593,958.

To all whom it may concern:

Be it known that. I, FLOYD C. KELLEY,

a citizen of the United States, residing at Schenectady, in the countyof Schenectady,

.5 State ofcNew York, have invented certain new and useful Improvements'in Metal Coatings (division of my application filed May 10, 1920,Serial No. 380,023), of which the following is a specification.

1 The present invention relates to the coating of cast iron with othermetal and particularly to the production of a composite article of castiron'and a non-ferrous rnetal. Great difficulty has been experiehced in1 causing cast iron to unite with a. non-ferrous metal, for example,copper, in such a way asto produce a thoroughly adherent coatlng. orvunion. 'Heating the metals to be united in hydrogen does not cause thecopper to 2 wet the cast iron as is the case when copper in a molten,state is brought into contact with steel in the presence of hydrogen.

' Fluxes likewise fail to produce an adherent coating between cast ironand copper, or

2 the like, when used in the. usual way in contact with air.

I have discovered that a homogenously adherent union between cast ironand a nonferrous metal of lower melting point, such as copper, silver orbrass can be produced by applying the molten non-ferrous metal to thecast iron to be coated in a reducing atc mosphere in the presence of aflux, particularly cryolite.

iron articles intimately united with brass or other suitable cupreousmetal, maybe produced. The cupreous metal in turn may be united with,alayer of other metal, such a for example, as Babbitt metal whichotherwise could not be integrally united with cast The accompanyingdrawing illustrates in section a bearing made by t e practice of aprocess embodying my invention.

, ;In accordance with one method of producing the article constitutingmy invention a body of cast iron 1 to be joined to a metal layer 2 ofcopper, silver or the like is heated in any convenient way, as forexample, in an ordinary gas flame, to about 750 to 800 (3., wherebythfesurface of the cast iron is In accordance with my invention, castlite,then is distributed uniformly over the heated surface as by applying thecryolite in powdered form upon the oxidized surface of the, cast iron.The cryolite is brought to fusion on the heated cast iron, and the ironsurface coated withcryolite flux is brought into contact with moltencopper, brass or the like in a hydrogen atmosphere. For example, apieceof copper wire may be wrapped about the cast iron and the iron withthe copper heated to the melting point of copper in a hydrogen furnace.If the cryolite has been properly distributed before melting thecop-per, a uniform coating 2, of copper results which when molten wetsthe cast lron'in such away as to resist mechanical separation when'solidified- In my opinion the heating of the-cast iron to about 750 to800 C. in an ordinary gas flame oxidizes the carbon out of the surfaceof the cast iron, and whatever oxide of the iron is formed issubsequently reduced by the hydrogen.

A layer of Babbitt metal 3 may be cast against the layer of copper.Babbitt metal is an alloy consisting of a preponderant amount of tin, alesser amount of antimony and a small percentage of copper. A bearingthus produced may be supported on a suitable frame 4. Only one-half ofthe bearing enclosing the shaft 5 has been illustrated. I

When cast iron is .to be coated with silver, I prefer to employ borax asa flux.

In the appended claims, Ihave set forth the novel features of myinvention with particular reference to copper, but I wish it to beunderstood that my invention is equally applicable to coating cast ironwith other metals, as for example, brass, and I mean by the appendedclaims to cover an article comprising cast iron united to metals otherthan copper having similar properties.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is,-

l. An article of manufacture comprising cast iron, a coating of cupreousmetal united with the cast iron, the surface of the iron at the junctionwith said cupreous coating containing less carbon than the main body ofsaid iron, and a layer of Babbitt metal united with said cupreous metal.I

2. An article of manufacture comprising cast iron, a coating of copperdirectly and 3. An article of manufacture consisting of a base of castiron, a coating of copper united therewith and a layer of Babbitt metalunited with said copper coating.

In witness whereof, I have hereunto set my hand this 10th day ofOctober, 1922.

FLOYD C. KELLEY.

